Mark Cowan lost 18 stone and started racing regularly
Mark Cowan, 47, completely turned his life around after weighing over 18 stone and being unable to jog down the road.
But after joining a running club last year, he's since run a total of 15 marathons and 51 competitive races – and shed nearly five stone in weight.
After taking on his mammoth challenge he has been nicknamed Forrest Gump after the character played by Tom Hanks in the film.
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I also had very low self esteem before, whereas it is the complete opposite now
Mr Cowan said: "My running club named me Forrest Gump because all I do is run.
"When I started running in 2014 I could not run ten metres without being out of breath.
"To run a marathon was never even a thought, dream or an achievable goal.
"But after running the London Marathon I decided I needed to up my game and challenge myself even more.
Mr Cowan was nicknamed Forrest Gump after Tom Hank's character
"So I set some goals and it just went on from there, I ran a marathon in under four hours and even ran four marathons in five days over Christmas."
The father-of-four ballooned to 18st 8lbs back in 2000 after he gave up smoking and piled on the pounds instead.
He's since managed to curb his previously dangerously high blood pressure after becoming addicted to running over the last couple of years.
Company director Mr Cowan, of Benfleet, Essex, said: "Before I really was unfit. I had a dangerously high blood pressure but I have gone from one extreme to the other.
"When I started running I was on blood pressure tablets which I was told were for life, but I'm happy to say I've been off them since the summer.
"I also had very low self esteem before, whereas it is the complete opposite now."
Mr Cowan started running in the summer of 2014 after him and his wife Jackie, 46, got a personal trainer to motivate each other to get fit.
He entered a couple of Tough Mudder events with Jackie later on in the year and then decided to take on the London Marathon in 2015 due to getting so fit.
The company director has also entered some Tough Mudder events
Now Mr Cowan weighs just 13st 10lbs after losing nearly five stone by running a 5k every morning on the treadmill.
He also swims and cycles to help ease his sore legs and before races his routine includes 200 sit-ups and at least 50 press-ups a day.
Mr Cowan is now a member of Benfleet Running Club with the team taking part in competitive races together throughout the year.
Mr Cowan added: "I have to say a massive thank you to my running partner Melanie Anthony who has run with me throughout the year.
"You can't do this amount of running on your own, you need support from family and your fellow runners."
The fitness enthusiast has run more than 50 races in a year
Some of Mark's races include the Halstead marathon, Southend half marathon and Chelmsford marathon in Essex.
But he has also travelled to Amsterdam to do a race there and has taken part in multiple runs in London.
Mr Cowan added: "I have inspired some of my friends and family to get fit and even go running.
"You also meet the most amazing people when you run a marathon as everyone has a story or reason to be there.
"I have helped others to finish races when they had struggled and it has been a year I will never forget."
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Mr Cowan initially raised £4,000 from his London Marathon in 2015 and also raised money for Lancaster School in Westcliff, Essex, where his son Anthony attends.
The money was used to buy a new minibus and he now donates to Whizz Kidz – a charity which provides equipment to disabled children.
Anthony, 18, has cerebral palsy and was given a wheelchair by Whizz Kidz which is why it is close to Mark's heart.
Mr Cowan and nursery worker Jackie are also parents to James, 19, Johanna, 16 and 15-year-old Charlotte.
To donate, visit https://whizz-kidz-london-marathon17.everydayhero.com/uk/mark-5
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